Cellular confinement systems serve to increase the load bearing capacity, stability and erosion resistance of materials which are placed within the cells of the system. A commercially available system is Geoweb.RTM. plastic web soil confinement system, sold by Presto Products, Incorporated, P.O. Box 2399, Appleton, Wis. 54913. Geoweb.RTM. cells are made from high density polyethylene strips which are joined by ultrasonic seams on their faces in a side by side relationship at alternating spacings so that when the strips are stretched out in a direction perpendicular to the faces of the strips, the resulting web section is honeycomb-like in appearance, with sinusoidal or undulant shaped cells. Geoweb.RTM. sections are light-weight and are shipped in their collapsed form for ease in handling and installation.
The web materials have been used extensively to provide road bases, subgrades or pavement systems. Structural foundations have been reinforced or stiffened with the web materials. Additionally, Geoweb.RTM. cells have been used to provide earth and liquid retention structures by stacking one web layer upon another, such as a stepped back design for hill slope retention. The Geoweb.RTM. cells also protect earth slopes, channels, revetments and hydraulic structures from surface erosion. Grass and other earth slope cover materials have been protected and stabilized through the use of the web cells. Geoweb.RTM. cells can be infilled with various earth materials such as sand, rounded rock, granular soils and aggregates, topsoil, vegetative materials and the like. Concrete and soil-cement or asphaltic-cement can also be used to infill the cells.
During installation and long-term operation of the web materials, the fill material and the webs may be displaced. Erosion below the web material may cause concrete infill to drop out of the cells. Concrete cannot be pre-cast in the web materials because the concrete fill would drop out of the cells as it was lifted and moved to the installation site. Applied forces such as hydraulic uplift and ice action may lift the web material or lift the fill material out of the cells. Translational movement of the webs may occur in channel lining applications, or when surface protection on steep slopes slides.
In an effort to overcome these problems, J hooks have been intermittently spaced along the face of some cell walls and driven into the ground to anchor the web material before the cells are infilled. The rounded portions of the J hooks extend over the tops of the cell walls to limit displacement of the web material. While this approach has limited displacement of the web materials in some applications, it has not been completely successful in preventing movement of the webs.